Yep, the jokers at least seem to fail pretty rapidly, and they tend to be pretty dear from Jabsco . So, yesterday I replaced mine with one from the knock-off TNC head folks... way less expensive and essentially identical to the eye. Works fine now, and I'll be interested to see if it lasts at least as long as the OEM parts. If I get premature (or really, MORE premature) failure, I will report here on CF.

Cheers,

Jim

__________________
Jim and Ann s/v Insatiable II now in the Southport area for slipping next week.

I believe it really is a "choker valve" but Joker became the oft used name...maybe because the joke's on us...should last longer than a few months...but, rather replace the joker and flapper than have back flow, and don't feel like a major refit to replace the head with something more substantial.

They seem to copy many of Jabsco's products and sell them here in Oz for about half Jabsco prices, more or less.

And my first product review comment is that after a day's usage it started leaking at the flange. A quick recheck showed that the thickness of the rubber flange on the joker was a bit thinner than the Jabsco one. Not being near a chandlery right now, I have glued a shim of 2 mm rubber on the flange, and the leak has stopped... for now.

Being a cheapskate has its drawbacks!

Cheers,

Jim

__________________
Jim and Ann s/v Insatiable II now in the Southport area for slipping next week.

Six years ago, I unbolted both my Jabsco heads from the deck and put them where they belonged............the dumpster. I replaced them with Raritan units and have the original joker valves in them. We live aboard for 8 months of the year.

__________________
Jim

We are what we repeatedly do. Excellence, therefore, is not an act but a habit."--Aristotle

I believe, though I haven't collected numerical data, that there is a relationship between the salinity of the water and the rate of crusty deposition on the joker valve. Mine last longer when I am further upstream within an estuary. I also believe that a dollop of vinegar (acetic acid) in the bowl slows this deposition. This is a much milder acid than the HCl mentioned above, but it still breaks down the scale.

Can't resist a reply . Lived aboard 5 years never replaced anything on either Jabsco head. Pour cookingoil in once a week and every so often half a litre of cheap vinager. Also have a sign " if you didn't eat it don't put it here"

never replaced anything on either Jabsco head. Pour cookingoil in once a week and every so often half a litre of cheap vinager.

Interesting...thanks malukusailor.

We haven't any problems yet, apart from our 'guest heads' being blocked by gravity back-flow (essentially not continuing the flush action long enough to pump the matter all the way into the tanks) against the joker valves. In the process of cleaning the blockages we observed the joker valves to be still flexible, albeit filled from behind with the blockage of course.

We also saw it suggested elsewhere to fill the heads with fresh water if they're not going to be used for a while, which we now do.

We might now add the cooking oil and vinegar as further preventative maintenance...